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71c10longbed 10-10-2018 02:46 PM

Engine build opinions
 
It is finally time in my build to send the 350 to the machine shop. It is the stock 71. My intent is to get more power, but not break the bank or drive-ability of the truck.

I have a high rise aluminum intake manifold and edebrock 600cfm carb I will be using. I have a set of long tube headers and HEI ignition that will also be used.
I currently have a 204/214@050 and plan on using it.

So for the build do I:
1. Put flat tops in with stock heads to increase compression (these are the stock 76CC heads that are fairly recently rebuilt). If I decide to upgrade heads later this somewhat limits my choice, but do I care with a relatively small cam??

2. Go back with the dish pistons and plan on upgrading to vortec heads somewhere down the line.

clay68c10 10-10-2018 03:46 PM

Re: Engine build opinions
 
What’s the budget? Are you going to have to bore the stock block and buy pistons?
If Vortec heads (and intake) are in the plan someday, can you get the Vortec crate engine for similar $ now?

Coley 10-10-2018 03:59 PM

Re: Engine build opinions
 
In my opinion your camshaft selection is going to be substantially more important for making power than all that bolt on stuff afterwards.....particularly if you are doing an upgrade to the heads later.

So...what kind of cam?....well, what kind of driver are you and where do you want to feel and experience your power? ....around town, streetlight to streetlight or passing power on the highway?

What sort of tires are you running on the truck? 15" or?....what is rear differential ratio? 3.07? 3:73? or?

...personally, I would always move towards a high lift cam...and not a long duration (ie: lumpity lumpity) cam on a truck.
The higher lift will generate more immediate torque and acceleration down low.

So what kind of driver are you and where do you want your power?

All good
Coley

71c10longbed 10-10-2018 04:07 PM

Re: Engine build opinions
 
The plan is to bore block with new pistons. Hopefully use existing crank and rods. I've got a brand new timing chain/gears so I'll save some $$ there.

Based on conversations with the machine shop, I am anticipating $1,000 - $1,500 max for a complete engine.

I guess my main question is can I make decent power with flat tops and stock heads?....

or are the vortecs so much better I need to plan on them? Plus there are additional costs with the vortecs - intake manifold, self-aligning rockers, valve covers.

I am kinda leaning towards stock heads and flat tops, because if I am not happy I can upgrade the heads later to something like this:
https://www.summitracing.com/parts/p...make/chevrolet

71c10longbed 10-10-2018 04:14 PM

Re: Engine build opinions
 
Quote:

Originally Posted by Coley (Post 8361205)
In my opinion your camshaft selection is going to be substantially more important for making power than all that bolt on stuff afterwards.....particularly if you are doing an upgrade to the heads later.

So...what kind of cam?....well, what kind of driver are you and where do you want to feel and experience your power? ....around town, streetlight to streetlight or passing power on the highway?

What sort of tires are you running on the truck? 15" or?....what is rear differential ratio? 3.07? 3:73? or?

...personally, I would always move towards a high lift cam...and not a long duration (ie: lumpity lumpity) cam on a truck.
The higher lift will generate more immediate torque and acceleration down low.

So what kind of driver are you and where do you want your power?

All good
Coley

I am looking for good torque and mid-range. 5000rpm tops is fine with me. I current have 255/70/15 tires on the truck with 3.07. The rear end will most likely get upgrade to 3.4 in future.

I currently have a 204/214 cam, lift is 421/444. The cam was a nice upgrade over stock while still having decent manners. I will be changing out the cam though.

sick472 10-10-2018 05:01 PM

Re: Engine build opinions
 
Quote:

Originally Posted by 71c10longbed (Post 8361212)

I guess my main question is can I make decent power with flat tops and stock heads?....

Yes you can. You should be able to get in the ballpark of 1 hp per cube by building your engine to need 91 octane (10:1 compression or there-abouts), but you will need to open the intake and exhaust ports to match some larger gaskets, and use long tube headers. There is obviously a lot more to it than that, but 350's have been making cheap HP for, well, ever! Your budget of $1500 might be a bit tight unless you have access to good affordable used parts, but it sounds like your on your way. The only things I would warn you about is that if you plan to modify the setup later...you need to mentally build two motors now so that you don't paint yourself in a corner, if you know what I mean.

71c10longbed 10-10-2018 05:17 PM

Re: Engine build opinions
 
Quote:

Originally Posted by sick472 (Post 8361239)
Yes you can. You should be able to get in the ballpark of 1 hp per cube by building your engine to need 91 octane (10:1 compression or there-abouts), but you will need to open the intake and exhaust ports to match some larger gaskets, and use long tube headers. There is obviously a lot more to it than that, but 350's have been making cheap HP for, well, ever! Your budget of $1500 might be a bit tight unless you have access to good affordable used parts, but it sounds like your on your way. The only things I would warn you about is that if you plan to modify the setup later...you need to mentally build two motors now so that you don't paint yourself in a corner, if you know what I mean.

Thanks. Painting myself in a corner is definitely what I want to avoid.

Just a bit more information - I have a set of vortec heads/intake manifold/bolts/gaskets etc. that I had planned on using. But I decided to install these on my boat, as it needs the hp boost more than my truck.

So now I think I am going flat top pistons and with the parts I already have (intake, carb, cam, headers, distributor), I think for $1500 I should be able to get close to 300hp which is all I want. Then I can always upgrade heads/cam later if I want more....

67 chevelle 10-10-2018 08:49 PM

Re: Engine build opinions
 
get vortecs now , forget the rest


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